gtpphase Help File

Computes a pulse phase for each event in input event file(s), and writes it to a FITS column in the file(s).

Usage: gtpphase evfile scfile psrdbfile psrname ephstyle ephepoch timeformat timesys ra dec phi0 f0 f1 f2 p0 p1 p2

This tool operates on input event file(s) to compute a pulse phase for a photon arrival time of each event, and writes it to the PULSE_PHASE column (by default) of the event file(s). Ephemeris information can be given in one of the following forms:

• Manually input the source (pulsar) location (for the barycentric correction), pulse frequency or period, and related information.

• Automatically extracted from a pulsar ephemerides database, available online.

If necessary, this tool reads the spacecraft orbit file and performs the barycentric correction and the binary demodulation to each photon arrival time on-the-fly.

Example: gtpphase

The simplest way to run the gtpphase tool, which may suffice for most applications, is for the tool to extract the information from a master pulsar database. The exact process the tool uses for choosing ephemerides is described below.

Another option is to supply the essential ephemeris information manually. For example, this may be useful when an ephemeris is not available in a database, but the necessary information is available in the literature. In the example shown below, the same values which were extracted from the database in the previous example were entered manually.

> gtpphase evfile=fakepulsar_event.fits scfile=simscdata_1week.fits \
psrdbfile=bogus_pulsardb.fits psrname="PSR J9999+9999" \
ephstyle=FREQ ephepoch=54870.0 timeformat=MJD timesys=TDB \
ra=111.11 dec=22.22 phi0=0.0 f0=112.345 f1=-2.345e-10 f2=3.45e-20